An online retailer or other entity may communicate with its customers by various communication channels. For example, the online retailer may originate short message service (SMS) messages to a mobile telephone number of the customer, voice calls to a telephone number of the customer, email messages to an email address of the customer, printed materials to a postal address of the customer, and so on. Without verification that the telephone numbers, email addresses, postal addresses, and/or other addresses have been accurately provided for the customer, notifications or other significant communications intended for the customer may be lost or misdirected.